Imagine you are riding a roller-coaster. It has chugged up the first hill and has come to a stop at the very top (see arrow). At this moment, which is higher, your potential energy or your kinetic energy?

if the roller coaster is almost stopped, the obviously the kinetic energy is almost zero. but on rising height, the potential energy increase. therefore, potential energy is higher.

Thank you! Could you help me with some of the other ones too?

A toy train has a mass of 2 kg and travels at a rate of 1.5 m/s. How much kinetic energy does it have when it's in motion? I think the answer is 3.0 J?

1/2*2*1.5^2 = 2.25J

Thank you! I have one more: How much potential energy does a 3 kg can of paint have when it is placed on top of a ladder that is 2.5 m in height? Is the answer 7.5J?

73.5J?

*

use m*g*h that is 9.8*2.5*3 = 7.3J you are right!!

Wait, it's 7.3J?

oops sorry, it's 73.5J

Ohh, ok :) Thanks!

Join our real-time social learning platform and learn together with your friends!